The development of NiCo₂O₄/PVP/PANI heterogeneous nanocomposites as an advanced battery-type electrode material for high-performing supercapacitor application

Recently, various electroactive materials composed of binary transition metal oxides (TMOs), and conducting polymers have been extensively studied, with the materials demonstrating great potential in high-performing battery-type electrodes. Furthermore, the development of heterogeneous nanocomposites is a versatile approach because of their well-defined surface morphology and the significant synergistic effect of the various species. In this study, NiCo₂O₄ (NCO) combined with polyvinyl pyrrolidone (PVP) and polyaniline (PANI) hybrid nanocomposites of NCO/PVP/PANI are newly developed using a facile hydrothermal method. The NCO in combination with PVP and PANI species provides the interconnected hierarchical characteristics by offering large electroactive sites that facilitate the charge transfer. The NCO/PVP/PANI_1.5 nanocomposites had a high areal capacity of 698.44 µAh cm⁻² at a current density of 4 mA cm^–2 and a remarkable capacitance retention of 86 % over 4,000 galvanostatic charge/discharge (GCD) cycles owing to its excellent synergistic effect of the rich faradaic redox reaction kinetics of metallic species, and highly conductive materials. Moreover, the proposed NCO/PVP/PANI_1.5 battery-type positive electrode was successfully assembled with an activated carbon negative electrode, resulting a hybrid device with a high energy density of 27.60 Wh kg⁻¹ at a power density of 874.9 W kg⁻¹ and excellent cycling stability. This research holds the significant promise for advanced heterogeneous materials in energy storage systems by describing the newly developed nanocomposites.